Lines Crossed
by piper maru duchovny
Summary: Once you cross the line from friends to lovers, it can't be undone. - Callie/Addison HS cheerleader/nerd AU.
1. Chapter 1

**For Rachael. Merry Christmas, babe. I know you love this trope and Caddison is the only pairing I knew I could write that you love and would work with it. So I hope I did it justice. (If it sucks, you better lie) I love you!**

**Disclaimer: I own nothing. **

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_But she wears short skirts, I wear t-shirts,  
She's cheer captain and I'm on the bleachers,  
Dreaming 'bout the day when you wake up and find,  
That what you're looking for has been here the whole time  
-Taylor Swift's You Belong With Me_

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"Arizona, you're not listening to me," she growled in frustration as she raked her hand through her raven locks and kicked at the leg of her bed frame before shooting the redhead on her bed an apologetic look. "No. Do not Calliope me, Arizona. You fucking slept with someone else!" Addison flinched and wrinkled her nose as she listened to the girl rant on the phone. "We're done. You live on another continent now and obviously you've found better things to do with your time than work on this long distance thing. I hope you're happy – honestly."

Casting aside the physics book that was on her lap, Addison moved to her knees and shoved the auburn hair back from her face before pushing her glasses up the bridge of her nose as the seventeen year old angrily hung up the phone. She reached out a hand and pulled her friend in for a tight hug. "She's an idiot, Cal. You deserve way better than she could ever offer."

"Thank you," Callie whispered as she bit back tears that threatened to fall as she let out a shaky sigh. "I just... Logically I knew it wasn't going to last when her dad got stationed in Germany but I just thought she would have the decency to let me know before she slept with someone else. And now I have to cheer in this stupid game? Ugh."

"Cal..."

She moved away from the hug and flopped down across the foot of her bed. "I just... hate her. Anyway, I'm sorry that I kicked the bed. Did you get your physics done?"

"Nah," she whispered and shook her head. "It's okay; it's just extra credit and it's not due until Monday anyway."

"Nerd," the brunette teased and pulled Addison's glasses off her face before placing them on her own. "Jesus, Addison, how do you see in these things?"

"Dork," the redhead countered as she stole her glasses back and put them where they rightfully belong. "They're fitted for my prescription, you moron. For you and your flawless vision they probably turn everything into that one Beatles video."

"Pretty much." Callie lifted herself up on her elbows and scrunched her face up for a second as the events of the day caught up with her. "You're coming to see me cheer tonight, right? Because if you don't and I'm stuck going to the dance after with all the jocks I might throw myself down the stairs just to break my leg and get out of all this."

"You really want me there?"

"No, I just asked you so we can all pull a Carrie on you."

"Ass." She smacked her with a pillow. "You know I don't fit in with all those jocks, Cal. I'm a nerd. That's my social sector, much to my mother's chagrin. It's where I belong."

"You are my best friend on the planet, Addison Montgomery, and you have been since we were in diapers. If I belong somewhere then you belong there too."

She tried to pretend her heart didn't skip a beat at Callie's words, tried to pretend she hadn't had a crush on her best friend for the last four years. "Fine, I'll go. Mother will be thrilled that I'm not spending another night at home doing extra credit and practicing my orchestra piece."

"Good," Callie told her with a grin. "Bizzy can get the stick out of her ass for a night and I get the prettiest girl in the whole school on my arm for homecoming."

"You big fat liar," Addison countered.

"Yeah," she confessed solemnly. "You're right. Nothing will ever dislodge the stick from Bizzy's ass. It's why she and my mother get on so famously."

"Shut up," the redhead ordered with narrowed eyes and a decidedly sharp poke to the brunette's ribcage. "I am so not the prettiest girl at school."

"You will be once we get you out of that muumuu you insist on wearing."

"It's not a muumuu."

"Uh-huh." A pillow barely missed Callie's head as she clambered off the bed and over to her closet that was busting at the seems with the latest fashions; the Torres family was never one to flaunt their money but there was no hiding that Callie was an heiress to a lofty family fortune, especially when it came to dress. She flicked through her clothing with a decisive eye as she rummaged through for something that might fit her friend who was just a slightly different build than herself. Luckily they were roughly the same height and Callie's closest ranged a myriad of sizes thanks to her mother putting her on a new diet every few months.

She plucked out a dark black gown and held it out for Addison's approval. "It should fit you," she promised. "It fit Aria last month and you two are closer in size than us."

"Fine," Addison relented. "You'll help me get ready after the game?"

"Of course," she agreed. "After I get not gross from cheering outside in October."

"Fair enough."

Callie tossed the dress on the foot of her bed before pulling out the one she planned to change into as well. She then grabbed her duffel bag and pulled out her cheer uniform so she could get ready for the homecoming game. Without a thought to the company in her room, she quickly shed all the clothes but her underwear before pulling on a sports bra and her uniform.

Addison watched her friend for a moment, reveling in the golden muscled expanse of her abdomen before she forced herself to look away as she fell back across the bed. "Hey," she forced her voice to work. "Callie?"

"Addie," she countered as she shimmied into the skirt.

"You know how I'm like eighteen, right," she asked, cursing herself for own stupidity. "And I've like never ever been kissed. Or anything even close to a kiss."

"Yeah," she responded slowly as she sat down on the floor to pull on her socks and shoes. "Do you want me to set you up with someone or something? You don't still have a crush on that tool, Derek, do you? Cause he's been hot and heavy all season with that freshman."

"No, no." She waved her hand as if to brush away the thought. "I just... I think I like someone though."

"Addison," she squealed as she dove onto the bed next to her friend, practically landing on her as their legs brushed and she grinned down at her. "That's so great! Who is it? Please tell me it's someone that will cause your mother to have a conniption fit. Please. I'll be so proud."

"Oh, it is definitely someone who would make Bizzy lose her damn mind," she promised with a heavy sigh. "I'll tell you soon, I promise. I just... I think they might like me too. Maybe. Probably not because I'm... me. But maybe. And I was just wondering how you... when the moment is right?"

"Kiss someone?" She shrugged. "You just know, babe. You can't make the moment happen if it's not there and when the moment is right... You'll just know."

"You are soooo helpful," she growled in frustration and pushed at her.

Callie laughed and flopped across Addison before moving so she was hovering over her. "Just don't settle, okay? You deserve the whole world, Addison Montgomery. Don't settle for someone who won't give it to you."

She nodded. "Would you give me the world?"

"In a heartbeat, babe," the raven haired girl promised and dropped a kiss to her forehead. "Sucks that you're not into girls."

Addison's heart hammered inside her chest and she wondered if this could be the moment. "Hey Cal?"

"Yeah?"

Self-doubt crept in at the last second. "You're going to be late for cheer."

"Dammit," Callie growled as she climbed off her friend. Racing over to the mirror, she grabbed her ribbons and make up case. "Grab the dresses and you can drive my car while I get myself presentable."

"Sure."

At the game, Addison sat on the rapidly filling bleachers as she watched the cheerleaders stretch and get ready for the game while the boys were warming up on the field. The Torres and Montgomery families had been friends since long before the girls had been born; both families being prominent in society had caused them meet and Lucia and Bizzy had fallen together like two peas in a pod. Callie and Addison had been put together since birth; they helped each other deal with all the crazy, always having each others backs even when their parents would turn on them. When Callie had come out during their sophomore year, Addison had gotten hopeful that the brunette might turn an eye her way but she'd been enthralled by the Captain's daughter that had been a transfer student that year and had transferred right back out at the end of their junior year and totally stomped on her best friend's heart. Callie and Arizona had been dragging the breakup out for months, wondering if they could fix their relationship before realizing there wasn't much there worth repairing anyway. Maybe, the redhead thought, she might finally have her chance.

Callie caught her eye from the edge of the field and gave her a salacious wink which brought a giggling smile to the redhead's face as she offered a small wave in return.

All through the game, Addison noticed that her friend would go out of the way to catch her eye. When the game was done, the brunette quickly broke off from the group of cheerleaders making their way out to the field to congratulate their boys and into the crowds of dispersing people to find her friend. "Hey," she called when she finally found her standing at the exit gate. "You're a pretty bench warmer."

"I am offended," she teased back. "I cheer with the best of them. Go team."

"Please," Callie countered. "You would have been much happier doing that extra credit."

"Yeah, I might have been happier doing homework than freezing my ass on a bench but I'm happier being here with you than I am doing homework."

"You say the sexiest things to me, Montgomery."

She laughed, trying ignore the blush making the way up her neck. "Yeah, yeah, yeah. Let's go make you pretty for that stupid dance."

"I'll sneak you into the locker room," Callie promised as she draped an arm around her best friend's shoulders and smiled as she snuggled in closer as they walked up the hill toward the school.

There was a half an hour to kill between the game and the dance so most of the cheer team had opted to go home and clean up before arriving fashionably late to the dance. Leaving Callie and Addison in a mostly vacant locker room. The redhead sat on the in front of the lockers and smiled as she listened to Callie in the shower, singing, and laughed when she would purposefully screw up the lyrics.

"You're such a moron," she called over the noise of the running water.

"Yeah but you love me anyway."

She smiled. "Yeah. I do."

When the brunette emerged wrapped in a towel, Addison forced herself to remember how to breathe. Once upon a time they had shared showers when they'd have sleepovers as children, it wasn't anything that she hadn't seen before. She cast her gaze downwards as she fiddled with the dresses hanging via the vent in the locker that belonged to the cheer captain.

"Are you sure you want me at this thing," she asked once more. "I'm sure Mark or somebody would go with you if you asked."

"Addison, would you stop?" Callie dropped onto the bench in her undergarments with a hair brush danging from her fingertips. "There is no one else in the whole world I want with me tonight. No one. No ex-girlfriends in Germany. No ex-boyfriend turned best friend. Just. You. I want you, Addison. Do you want me too? Or is that why you're trying to get out of this whole thing?"

"I want you too," she whispered. "Of course I do. You're Calliope." She stressed the girl's proper name. "Pretty sure I would have be brain dead to want to be anywhere other than on your arm."

"Then why are you doing this?"

"Because I'm me, Callie!" Tears pooled under her eyes and she willed them not to fall. "I'm your best friend, your lackey. I may come from money but you and I both know that I am nothing in this school other than a brain. You are cheer captain for crying out loud. You could have anyone you want. I'm just... I don't want to be a pity date."

"Addie?"

"Yeah," she sniffled.

"You're an idiot."

She sniffled again. "Okay."

"I have never given a damn about those stupid high school stereotypes," Callie informed her. "You know this. You are my best friend and so beautiful and I love you. And, I swear to god, if anyone says anything about you being a pity date – yourself included – I am going to kick their asses. I am lucky to have you on my arm!"

"Cal..."

"Look, I know it's not the most romantic proposal but would you please, please, please do me the great honor of being my date to homecoming?"

"Like a date?"

"Yeah." She reached out and tucked a lock of hair behind her ear. "Sweetheart, I may not have your GPA but I'm far from stupid. I can put two and two together when it's laid out in front of me. Be my date tonight?"

"Really?"

"Addison Adrienne, I swear to god... Do not make me beg for this."

"Like girlfriends," she asked, needing clarification.

"Like friends who are attracted to each other and want to see where this thing is going," Callie told her. "And maybe girlfriends. Eventually. When I'm not just getting out a breakup."

"That's fair," she told her with a grin. "Does that mean I get a goodnight kiss?"

"You can have anything you want so long as you let me finish getting dressed and stop freaking out on me."

She smiled. "I can do that."

"Good." And she was rewarded with a peck on the cheek.

Then a slow dance.

And finally a kiss goodnight.


	2. Chapter 2

**Back by popular demand and heavily inspired by Taylor Swift. Really, I was still infatuated with this verse and Rachael said she wouldn't be opposed to reading more so I decided to go ahead and crank this out. Hopefully it doesn't suck out loud and if it does well then... I'm just going to blame this nasty case of bronchitis I'm fighting. Thank you to everyone who reviewed the first chapter!**

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_you made a rebel of a careless man's careful daughter  
-Taylor Swift's "Mine"_

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She stood in front of her full length mirror frowning at her body as she pulled at her sweater, picking at the fraying waist of her favorite pair of jeans. Her auburn hair fell over her shoulder in a messy braid as she contemplated bothering with her contacts of not before deciding it was better if she didn't – the last thing she wanted to do was spend her first date with Callie blinking like crazy because her contacts felt weird. Addison sighed heavily; her first date with Callie was that evening and she wanted to look nice but an inconspicuous kind of nice because she still had to make it downstairs and out the front door past both her parents who would question things if she looked too good as she made her way out the front door.

A glance at the clock told her that she didn't have time to worry about it any longer, Callie would be waiting in her driveway within moments. She slung her bag over her shoulder and sprinted down the front staircase, hoping she could dart out the front door without an inquisition but her mother's throat clearing stopped her on a dime. "I'm going out with Callie," she explained quietly. "It's Friday night and I've already got all my homework done."

"You two have been spending a lot of time together lately," her father commented as he glanced up from the papers he was grading.

"She's my best friend," she offered by way of explanation. "We're always together."

"Addison," Bizzy began and the redhead barely refrained from rolling her eyes. "Socializing is wonderful for a woman of your age but wouldn't you rather spend time with Aria or someone... Not like Calliope."

"Mom," Addison whined. "Please tell me you're not toting Lucia's line of crap. Callie is not any less human or deserving of friends just because she's into girls and guys."

"I'm just saying that you have an obligation to this fam-"

"I have an obligation to my friend that I said I would spend time with this evening," Addison cut her mother off, something she had never dared to do before. "I am almost eighteen years old, mother, and I am going out with Callie tonight. I'll probably stay the night over at the Torres' tonight. You and Lucia can discuss it all at the club." With that, she turned on her heel and stormed out of the house with a rattling slam to the door behind her. It was liberating in a way that made her nearly hyperventilate; for years she had been a victim of her mother's bullying and to finally stand up to her felt freeing in a way she hadn't expected.

Callie's car was idling at the end of the driveway and she sprinted the distance to the car, throwing herself in and after casting a quick glance behind them to make sure they didn't have an audience she pressed her lips to the brunette's. It was a quick kiss, daring and fast, and ended soon after it began. She breathed against Callie's lips as she grinned. "Hi."

"Hi," Callie laughed as she pulled away to put the car in drive and take off. "What's gotten into you?"

"I may have told off my mother on my way out the door," she spoke quietly.

The brunette nearly slammed on the brakes. "What? You, Addison Adrienne Forbes-Montgomery, stood up to Bizzy? Are you for real?"

"She tried to keep me from seeing you," Addison explained as she tossed her bag on the floorboard and relaxed into her seat, angling her body so she could look at the driver. "I just got so angry that she would try to keep us apart because god forbid I do something unseemly. You're my best friend. She's not keeping me away from you."

At a vacant red light, Callie leaned over and pressed her lips briefly to the redhead's. "I'm a lot more than your best friend, I think."

"Yeah but she doesn't need to know that... yet." Addison sighed. Coming out hadn't been a walk in the park for Callie but Callie was confidence personified – she had jumped in and powered through the mess that followed, never looking back and taking all the consequences that followed. Addison was much more timid, reserved, and she wanted desperately to make her parents happy. "I... I'm not ashamed or anything."

"I get it," Callie promised. "That's something you have to do on your own time, Addie. You don't have to explain it to me, okay? Just because I'm out doesn't mean that you have to be."

"Thank you," she breathed.

"Plus, my mom be ready to douse me in holy water but daddy's come around pretty well... I somehow doubt that Bizzy and the Captain would go quite so easy on you."

Addie laughed. "No. I'm pretty sure that Bizzy's head would spin around while she vomited split pea soup."

"That's disgusting." Callie shook her head as she glanced over at the redhead riding shotgun. When she had broken up with Arizona, this was the last thing she had expected to happen; sure, she had always thought Addie was beautiful and brilliant but she never thought she would look her way twice when she could have any guy that she wanted if she ever looked up from her books. "So what's in your bag, bookworm? You know this is a date, right?"

"Clothes," she explained. "I figured I was staying at your place tonight."

"Really, Montgomery, you think I put out on a first date? I may be a cheerleader but I'm not that easy."

Addison sputtered and Callie laughed heartily before she got a punch to the shoulder. "You are mean."

"Yes, I am." She shook her head and smiled. "Of course you're staying the night; there's no way I can send you home to Bizzy after you just started a war."

"Gee thanks." Addison rolled her eyes. "There may also be a book in there. _Cosmos_ by Carl Sagan."

"My girlfriend is such a nerd."

The redhead would be a liar if she said her breath didn't hitch at the label.

It took the better part of thirty minutes to get the restaurant outside of their hometown; it was probably an unnecessary precaution but it was one Addison appreciated nonetheless, though as far as she was concerned they could have at McDonald's at the city park and it would have been the perfect date. She had never been on a date before (unless you counted Mark Sloan taking her skating in sixth grade) and Callie intended to pull out all the stops. The restaurant was a small family owned affair on the beach and Callie quickly rounded the car to greet Addison after she parked.

Their fingers laced together and the redhead canted into her side as they walked towards the front door. "Cal, this is too much."

"Don't worry about it," she whispered in her ear. "Daddy reinstated my allowance and made sure mami knew that he wasn't going to disown me no matter how much she damned my less than heterosexual soul."

"Cal-"

"Addie," Callie sighed. "Let's just enjoy tonight, okay?"

"Okay," she relented and tilted her head to kiss Callie's jaw. "Hey Callie?"

"Hmm?"

"I'm really glad we're doing this," she confessed.

The brunette smiled and turned to catch her a quick kiss before opening the door for her. "Me too, Addie. Me too."

After dinner, they found themselves walking along the shoreline as the sun sank below the horizon and Callie hummed some old tune she had picked up from her grandmother on a family vacation back to Cuba several summers prior. Addison walked slightly ahead, stopping to pick up stones and cast them back into the water as they walked before Callie caught her hand and pulled her in for a slow kiss, their most passionate to date. The redhead pulled away breathlessly and grinned. "What was that for?"

"Just because," Callie explained.

"It's getting late," she lamented. "We should get going soon."

"Or we could just camp out here on the beach all night," Callie suggested.

"Now you're just trying to kill our mothers," the redhead countered with a chuckle.

"Or we could runaway together."

"After graduation," Addison told her with a grin. "I'm not running away without my diploma."

"Ugh," Callie sighed. "Nerd."

"It's part of why you find me so hot," Addison countered.

"Fair enough."

The night ending found them back at the Torres mansion and sprawled across Callie's bed in their pajamas. Addison leaned back against the headboard with fingers lost in Callie's riotous curls and the brunette's head in her lap as she read aloud from the book she had brought with her, stopping every few pages to explain something that the other woman had a question about.

"You two are disgusting," Aria Torres complained as she entered the room without knocking and flopped across her big sister's bed.

Addison chucked a pillow at the fifteen year old and Callie gave the girl a slight kick in the ribs. Growing up together, the redhead was close with both the Torres sisters but as seniors in high school the two and a half year age gap between them and the freshman Aria had never felt wider. Still, in spite of Lucia's misgivings, the girl remained ever faithful to her big sister and Addie knew she would walk through fire for Callie's happiness.

"Get out of my room, you brat," Callie ordered as she shoved at her sister with her foot.

"Fine," Aria whined. "Just thought you two should know that mami is on the phone with Bizzy and neither of them sound very happy."

"What else is new?"

"Mami promised Bizzy something about bed checks," the girl explained. "Thought you should know."

Callie sighed. "You're a good snoop, Ari."

"Should I go sleep in Aria's room," Addison asked.

"No way in hell," Callie told her. "Just... I'll sleep on the floor tonight – you can take the bed."

"I am not taking your bed."

"You are too," she argued. "My girlfriend is not sleeping on the floor."

"Well my girlfriend isn't getting kicked out of her own bed," Addison countered.

Aria rolled her eyes. "Why don't you both share the bed like you always do and have always done since you were little kids? Mami might think it's weirder if she comes in and finds one of you on the floor when there's supposed to be nothing going on."

"She has a point."

"I always do," Aria interjected. "And I will sleep on the floor. So the parents think it's nothing but a sleepover. Just... Keep your hands to yourselves."

"We can do that."

"Thank you, Aria," Addison told her friend and pulled her in for a hug. "I love you, even if Callie thinks your a big pain in the ass."

"I've always told daddy to trade you two," Aria countered as they both looked at Callie who glared back at them.

Addison laughed. "You know you're my favorite, Cal."

"Yeah," Aria agreed. "She doesn't want to suck face with me."

"No one wants to suck face with you, twerp," Callie countered as she kicked at her sister and sat up to pull Addison to her, her lips finding the redhead's neck. "Get out of my room and come back at bedtime, you pain in the ass."

"I'm gone," Aria promised. "Get all the face sucking out of the way before I get back, please."

When the door closed behind Aria, Addison turned and quirked an eyebrow at Callie. "Girlfriend? Twice in one night."

"Well," she sighed. "If the shoe fits then wear it."

"Mhmm. You know what you should do," she asked. "Kiss your girlfriend."

"That's a damn good plan."

That night when Lucia Torres went to perform the promised bed check she found her youngest daughter sprawled across the foot of her oldest daughter's bed, Callie curled up in a ball against the headboard, and Addison on top of the covers and nearly falling off as Aria's legs pushed against hers. Sighing peacefully, she left the room happily to report to her best friend that nothing was amiss with their daughters to the best of her knowledge.


End file.
